Semitransparent inverted polymer solar cells using MoO3/Ag/WO3 as highly transparent anodes

We demonstrate semitransparent inverted polymer solar cells with highly transparent anodes. The structure of the anode is made up of molybdenum trioxide (MoO3)/silver (Ag)/tungsten oxide (WO3). The inner MoO3 layer is introduced as a buffer layer to improve hole collection, while the outer WO3 layer serves as a light coupling layer to enhance optical transmittance of the photovoltaic device. The dependence of device performances on thickness of the outer WO3 layer was investigated, and the transmittance and reflectance of MoO3 (1 nm)/Ag(10 nm)/WO3(x=0, 20, 40, 60, and 80 nm) electrode are compared. A high transmission of 90% was achieved for semitransparent inverted polymer solar cells with a 40 nm thick outer WO3 layer.